Sources of various systematic uncertainties on the branching fraction calculation are shown in Table REF .
The uncertainty due to the total number of \(B\bar{B}\)  pairs is 1.4%.
The uncertainty due to the charged-track reconstruction efficiency is estimated to be 0.35% per track
by using partially reconstructed \(D^{*+} \rightarrow D^0(\pi ^+\pi ^-K^0_S)\pi ^+\)  decay samples.
The uncertainty due to the subdecay \(J/\psi \rightarrow \ell ^+ \ell ^-\)  branching fraction is based on the world average value [1]}.
The uncertainty due to the photon detection efficiency in the barrel region (\(33^{\circ } < \theta _\gamma < 128^{\circ }\) , where \(\theta _\gamma \)  is the polar angle of the photon) is studied using a radiative Bhabha sample,
and \(B^0 \rightarrow K^{*0} \gamma \)  elsewhere [2]}.
The uncertainty due to the \(X(3872) \rightarrow J/\psi \rho ^0\)  generation model is studied by comparing the signal MC samples generated with helicity distributions \(\cos \theta \)  (which is taken for the central value of efficiency), \(\sin ^2\theta \) , and \(1+\cos ^2\theta \) .
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